Synthesis,characterization, and antitumor activity of novel tumor-targeted platinum(IV) complexes

Four tumor-targeted platinum(IV) complexes with ammonia and cyclohexylamine as the carrier groups and biotin as the axial group were designed, synthesized, and characterized. In vitro evaluation of the antitumor activity of complexes C1–C4 against lung cancer cells (A549), liver cancer cells (SMMC-7721), breast cancer cells (MCF-7), and colon cancer cells (SW480) was carried out. Complex C3 had the best cellular activity. Compared with cisplatin, complex C3 showed good anticancer activity against A549 cell line,complex C3 (6.34±0.44) is 3 times more cytotoxic than cisplatin (19.40±0.71),and against MCF-7 cell line complex C3 (4.22±0.11) is 5.4 times more cytotoxic than cisplatin (22.96±0.58), and against SW480 cell line complex C3 (6.65±0.60) is 3.4 times more cytotoxic than cisplatin (23.15±0.22). (Table 1) Axial chloride increased the redox power of complex C3 to increase the intercellular accumulation and the introduction of mixed amine had the ability to overcome cisplatin resistance. Complex C3 works best on MCF-7, then SW480, A549, and SMMC-7721. Thus, complex C3 is targeted by the axial introduction of biotin.